Multi-jet spray nozzle with a movable shutter member

ABSTRACT

A spray nozzle for expelling a jet of fluid, particularly suited for use in massaging the gums by the use of a liquid and for cleaning the teeth, comprises a nozzle body which defines an inner fluid cavity therein and an opening which is limited by a seating surface. A freely-movable shutter member is contained within the inner cavity in the spray nozzle and is arranged so that a bearing surface of the shutter member is pressed against the seating surface of the opening to cover the opening under the action of a fluid pressure. The seating surface of the opening and/or the bearing surface of the shutter member cooperate to define the nozzle aperture having at least one groove which permits passage of the fluid from the inner cavity of the spray nozzle to the exterior thereof. A number of possible configurations for the movable shutter member are disclosed. The grooves which define the nozzle apertures may be located either on the seating surface of the opening in the nozzle body or on the exterior surface of the movable shutter. Preferably, the nozzle is made from a plastic material, or from a plastic material with a metal insert.

United States Patent Jousson. June 19, 1973 [54] MULTI-JET SPRAY NOZZLEWITH A MOVABLE SHUTTER MEMBER Primary Examinen-Richard A. Schacher [75]Inventor: Pierre J. Jousson, Geneva, Atmmey Lane Altken Dunner & ZlemsSwitzerland 57 ABSTRACT [7 3] Assignee: Institut de Recherche Woog,Geneva, 1

S i l d A spray nozzle for expelling a jet of fluid, particularly suitedfor use in massaging the gums by the use ofa liq [22] Filed: July 7,1971 Appl. No.: 160,280

TO FLUID PUMP uid and for cleaning the teeth, comprises a nozzle bodywhich defines an inner fluid cavity therein and an opening which islimited by a seating surface. A freelymovable shutter member iscontained within the inner cavity in the spray nozzleand is arranged sothat a bearing surface of the shutter member is pressed against theseating surface of the opening to cover the opening under the action ofa fluid pressure. The seating surface of the opening and/or the bearingsurface of the shutter member cooperate to define the nozzle aperturehaving at least one groove which permits passage of the fluid from theinner cavity of the spray nozzle to the exterior thereof. A number ofpossible configurations for the movable shutter member are disclosed.The grooves which define the nozzle apertures may be located either onthe seating surface of the opening in the nozzle body or on the exteriorsurface of the movable shutter. Preferably, the nozzle is made from aplastic material, or from a plastic material with a. metal insert.

44 Claims, 11 Drawing Figures PATENIED JUI 9 FIG. /0.

INVENTOR PIERRE J. JOUSSON ORNEYS MULTI-JET SPRAY NOZZLE WITH A MOVABLESHUTTER MEMBER BACKGROUND OF THE INVENTION This invention relates to aspray nozzle for spraying a jet of fluid or liquid. More particularly,this invention relates to a spray nozzle for spraying a plurality ofpulsated jets of liquid for massaging the gums and cleaning the teeth.Still more particularly, this invention relates to a spray nozzle havinga movable shutter member which largely eliminates clogging of the fluidapertures in the nozzle body and which facilitates cleaning of thedevices.

A number of spray nozzles for controlling the passage of a fluid areknown to the art. In particular, the art has produced a number ofdevices for cleaning the teeth and for massaging the gums which utilizespray nozzles of the general type described in this description. Thus,spray nozzles of this general type are known to the art which, whenused, are connected to a liquid pump which projects a pulsated jet ofliquid. An example of such an oral lavage device utilizing one type ofspray nozzle is disclosed in the patent to Mattingly, US. Pat. No.3,227,158, issued Jan. 4, 1966.

It is also known in the art to utilize such a spray nozzle as one of anumber of interchangeable heads which may be alternatively mounted uponan implement for treatment of the human body. Such devices comprise ahydraulic motor for mechanically driving a tooth brush which can befastened on the implement and other devices which can be mechanicallydriven. Examples of such devices are disclosed in the patents to M- ret,US Pat. No. 3,536,065, issued Oct. 27, 1970, and Swiss Pat. No. 471,460,as well as in the German published application No. 1,802,838. In thosedevices, a liquid pump to be connected to the implement either operatesthe hydraulic motor in the implement or, after shifting the position ofa valve, provides a spray nozzle with a fluid through a secondary ductadapted to the implement.

While the art has provided a spray nozzle with one spray aperture fordischarging a dense jet of liquid, it has been found advantageous toprovide the spray nozzle with a number of distributed spray apertures,each having a relatively small outlet cross section. Such spray nozzleshave been disclosed in applications assigned to the assignee of theinstant invention as demonstrated in the Swiss patent specification No.16231/69 and in United States patent applications Ser. Nos. 887,586 and887,587, each filed on Dec. 23, 1969. With spray nozzles of these kindsin which the spray apertures preferably have very small diameters, forexample in the ranges of 0.1 to 0.5 mm., a substantial difficulty isencountered in that these relatively small apertures may become ratherpromptly stopped by dirt, accumulations of dentifrice or other debris.Such accumulations in these apertures generally can be removed only withsome difficulty, for example by passing air through the device underpressure to force the removal of the accumulation or by using a probe,such as a metallic needle, to remove theaccumulation from the apertures.Both cleansing operations are time consuming and inconvenient to theuser.

It is thus an aim of this invention to provide a spray nozzle of thetype described which, while using apertures as small as desired,practically excludes the possibility of plugging such apertures withaccumulations or debris. Moreover, even if such an accumulation exists,it is also an aim of this invention to provide a spray nozzle in whichthe cleansing of the minute apertures is readily accomplished withoutdismantling the spray head.

It is an additional aim of this invention to obtain a plurality of jetsof fluid having different converging or diverging shapes with differentstructures of the spray head since, in particular applications, diversetypes of sprays are sometimes desirable. By way of a particular example,plural jets of fluid which converge at a predetermined distance may bedesired in one application while jets in which the streamlines areessentially parallel, cylindric, or diverging may be desired for otherapplicatioris. It is thus an aim to provide simple nozzle structureswhich can produce any of these jet shapes as desired.

It is also an object of this invention to provide a spray nozzle whichcan produce a converging liquid jet which can be focused at apredetermined distance from the spray nozzle, for example, at a distanceof 8 to 12 mm. In this manner, the energy of the liquid concentrated atthe focus can be employed by the user to remove the impurities adheringbetween the teeth. On the other hand, when the device is utilized formassaging purposes, and particularly for massaging the gums, the spraynozzle may be held at a distance correspondingly closer or further fromthe point to be treated so that the liquid impinges on the gums in theconverging or diverging regions of the jet. Thus, the effect of theforce applied to the gums may be somewhat controlled by the user.

These and other objects of this invention will become apparent fromreview of the accompanying written description of the invention taken inconjunction with the accompanying drawings.

SUMMARY OF THE INVENTION Directed to overcoming the difficulties in theprior art and achieving the aims and objects mentioned above, a spraynozzle according to the invention comprises a nozzle body which definesa cavity therein and an opening communicating between the exterior ofthe nozzle body and the cavity. A freely-movable shutter member islocated in the cavity in such a manner that the shutter member may bepress-ed against the seating surface on the opening by the action of afluid, such as a liquid under pressure, to substantially cover theopening. The seating surface of the opening or the bearing surface ofthe shutter member engaging the seating surface of the opening have atleast one groove, which, when the shutter member is pressed against theseating surface, acts as a nozzle aperture for the passage of the fluidfrom the interior of the spray nozzle to its exterior.

In this manner, the shutter member, which is freely movable in the innercavity of the nozzle body, covers the opening in the body only if thereexists some fluid pressure acting against the shutter member. Under thiscondition, the fluid may escape through the aperture or aperturesdefined respectively by the groove or grooves on either of the seatingsurface of the opening or on the accumulate in the aperture orapertures. Because of the mobility of the shutter member, particlesremaining in the grooves are generally freely detached from the grooveor grooves. In addition, a simple rinsing or brushing of the seatingsurface of the shutter head after each use will suffice to readilyremove the dirt or accumulation from the exposed grooves. These featureshave substantial advantages over the types of spray nozzles which mustbe dismantled for cleaning or probed with a needle or the like to removeaccumulations in the apertures.

It is further a characteristic of the invention that the shape of thegrooves on the seating surface of the opening or on the bearing surfaceof the shutter member can be selected so that a desired pattern may beprovided to the outgoing jet of liquid. By choosing particular grooveshapes and characteristics, converging, parallel, cylindric, ordiverging jets of liquid may be obtained in a relatively simple manner.

A converging jet ofliquid focused at a predetermined distance from thespray nozzle, for example at a distance of 8 to 12 mm., is convenient inthat the energy of the liquid concentrated at the focus can be employedby the user to remove particles of impurities adhering between theteeth. On the other hand, when the jet is used for massaging purposes,and particularly for the massaging of the gums, the spray nozzle needonly be held at a distance correspondingly nearer or further from thepoint to be treated so that the liquid emerging from the spray nozzlemay impinge upon the gums in the converging or diverging region of thejet.

Structurally, it is convenient for at least one of the surfaces of theshutter member or the opening to be tapered so that a portion of theshutter member may partially enter into the opening and be retainedtherein under pressure without being expelled from the nozzle body. Theseating surface and the bearing surface advantageously can convergeoutwardly in such a manner that the bearing surface of the shuttermember tapers more rapidly than the seating surface of the opening. Inthis latter case, the bearing surface of the shutter member abutsagainst the opening in essentially a line of contact so that thetolerance requirements assigned to the spray nozzle to achieveasatisfactory sealing of the opening are small. These tolerances, asidefrom the to]- erances of the grooves, are factor which lead to a moreeconomical manufacturing process for producing the spray nozzle.

Other convenient embodiments of the spray nozzle according to theinvention will be better explained by consideration of the drawingswhich represent a number of embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 shows a cross sectional view of a spray nozzle with a movableshutter member according to the invention wherein the shutter member isdefined by a body of revolution, the axial section of which is generallyU- shaped, for producing converging jets of fluid;

FIG. 2 is a view of an embodiment of the spray nozzle according to theinvention, partially in cross section, which utilizes aspherically-shaped shutter member coperating 'with a curved seatingsurface on the opening for producing parallel or cylindric jets offluid;

FIG. 3 is a view of an embodiment of the spray nozzle of the inventionpartially in cross section and similar to the embodiment of FIG. 2,which utilizes a spherically shaped shutter member cooperating with aconical seating surface on the opening for producing diverging jets offluid from the nozzle body;

FIG. 4 is a cross sectional view of an embodiment of the spray nozzle ofthe invention wherein the shutter member comprises a generallyspherically-shaped head portion and a rearwardly protruding projectionfor producing parallel or cylindric jets of fluid;

FIG. 5 is a view of an embodiment of a spray nozzle of the invention,partially in cross section, and similar to the embodiment of FIG. 4,wherein the grooves are located on the spherically-shaped head portionof the shutter member for producing converging-diverging jets of fluid;

FIG. 6 is a cross sectional view of an embodiment of the spray nozzle ofthe invention wherein the shutter member includes a shaped projectionwhich protrudes outwardly through the opening in the spray nozzle toproduce diverging jets of liquid;

FIG. 7 is a cross sectional view of an embodiment of the spray nozzle ofthe invention having a conical shutter head mating with a conicalopening for producing converging-diverging jets of fluid; and

FIGS. 8-11 show a front view of the spray nozzle according to FIG. 1illustrating different cross sectional shapes for the grooves whereinFIGS. 8 and 9 illustrate variously-shaped grooves on the seating surfaceof the opening and FIGS. 10 and 11 show the variouslyshaped groovesarranged circumferentially on the shutter members.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a spraynozzle according to the invention comprises a nozzle body, designatedgenerally by the reference numeral 15, which includes a rear housingmember 16 and a forward housing member 18. As shown, the rear housingmember 16 is hemisphericallyshaped and includes an inlet portion 17connected to the housing 16. The inlet portion 17 is preferablyintegrally formed with the housing 16. The forward housing member 18 isconnected to the rear housing member 16 such as by a threaded engagement(not shown) at the engaging surfaces 19 or by other suitable means forproviding a fluid-tight connection.

The nozzle body 15 may assume a variety of shapes. For example, the rearhousing may be generally cylindrical and closed on the rearward surfaceand arranged for receiving the forward housing member as an insert inthe open forward end of the rear housing. This alternative isrepresentatively shown in FIG. 2.

The inlet portion 17 of the spray nozzle 15 forms a handle for theconvenience of the user. A fluid inlet conduit 20 is formed in the inletportion 17 of the spray nozzle 15 to permit the passage of fluid, forexample, through a flexible conduit (not shown) from a fluid pump (notshown) to the interior of the spray nozzle 15. In accordance with theteachings in the art, the fluid provided in the conduit 20 from thefluid pump may be a pulsated flow of liquid. On the other hand, thespray nozzle 15 together with an inlet portion 17 may be adapted for useon a known hand implement which is connected to a liquid pump.

The rear housing 16 and the front housing 18 together define a cavity 22within the spray nozzle 15. The front housing 18 defines an opening 23which communicates between the exterior of the spray nozzle and thecavity 22. Preferably, the cross sectional configuration of the opening23 is circular. A freely-movable shutter member 24 is located in thecavity 22 of the spray nozzle 15. The shutter member 24 has the shape ofa body of revolution comprising a generally hemispherical forwardportion 25 and a generally cylindrical rearward portion 26. The shuttermember of FIG. 1 is thus generally U-shaped when viewed along its axialsection.

The outwardly tapering limiting wall of the opening 23 in the fronthousing 18 forms a seating surface.27 in the front housing 18. Theseating surface 27 is adapted for receiving the semi-circularly shapedforward portion 25 of the shutter member 24. The seating surface 27 alsodefines a plurality of circumferentially spaced grooves 29 which,cooperation with the shutter member 24, define the apertures in the headof the spray nozzle when the shutter member is disposed in contact withthe opening 23.

The possible free clearance for the shutter member 24 is limited by theinner portion 31 of the wall of the rear housing member 16 opposite tothe opening 23, so that the shutter member 24 is not permitted to slidecompletely inwardly away from the opening 23. In this manner, theshutter member 24 is maintained in its required orientation to obtainthe covering position relative to the opening 23 shown in FIG. 1, whilethe inner portion of the seating surface 27 of the opening 23 aids inguiding the shutter-member 24 into the position shown in FIG. 1 whenfluid pressure is applied to the nozzle body through the conduit 20.

In the absence of a fluid pressure from the fluid pump to the interiorof the spray nozzle 15, the shutter member 24 within the cavity 22 canmove freely inwardly from the position shown in FIG. 1 to expose theseating surface 27 and the circumferentially spaced grooves 29 in theopening 23. Thus, when the shutter member 24 is in that position, thegrooves 29 may be readily cleaned when desired by rinsing with water orby brushing. This feature is particularly advantageous when the fluid isa liquid antiseptic solution or a solution containing a dentifrice. Inthis manner, the grooves 29 in the opening 23 (as well as a portion ofthe interior of the nozzle 15) may be readily cleaned after each use.

When a fluid under pressure is applied to the interior of the spraynozzle 15, the shutter member 24, under the pressure of the fluid, ispressed from within the cavity 22 of the spray nozzle 15 against theseating surface 27 of the opening 23 so that the region of the bearingsurface of the shutter member, indicated by the reference numeral 30,effectively seals the opening 23 except for the presence of aperturesdefined by the grooves 29. Thus, the fluid from the fluid pump canescape from the interior of the nozzle body 15 only through theapertures defined by the grooves 29.

Due to the outwardly converging conical shape of the seating surface 27,the spray nozzle 15 of FIG. 1 delivers a converging jet of fluid asshown by the streamlines designated by by the reference numeral 32a. Theconverging streamlines 32a are focused on a focal point, designatedgenerally by the reference numeral 32, which is conveniently located ata distance of about 8-12 mm., and preferably about 9-10 mm., from thefront surface of the spray nozzle 15 so that the energy of the fluidconcentrated at the focal point 32 may be used particularly for cleaningimpurities which stick in the spaces between the teeth. For rinsing, andfor particularly massaging the gums, the user of the spray nozzle 15 canemploy the converging region or the diverging region of the jetrespectively nearer to or further from the nozzle body 15 relative tothe focal point 32 by maintaining the nozzle head 15 at a lesser orgreater distance from the point to be treated.

After interruption of the fluid supply to the nozzle body, the shuttermember 24 again is freely movable to expose the seating surface 27 sothat practically no par ticles or impurities can remain in the grooves29, a dif ficulty which frequently occurred with spray nozzles havingtiny apertures as has been previously described. A brief rinsing withwater after each use of the spray nozzle 15 suffices generally to removethe remaining particles from the grooves 29. If stubborn particles remain, a light brushing will suffice to remove those particles from thegrooves 29 as well.

The cross sectional configuration of the grooves 29 may be formed in avariety of shapes or configurations as desired as will be described inconnection with the embodiments of FIGS. 2-7. Moreover, the grooves 29may be located in either the seating surface 27 of the.

opening 23 as shown in FIG. 1, or in the bearing surface 30 of theshutter member 24, as will be described in connection with FIGS. 8-11.

FIGS. 8 and 9 are schematic frontal views of the spray nozzle 15 asdisclosed in FIG. 1 showing two possible alternative cross sections forthe grooves 29. In FIG. 8, the front housing 18 is shown defining theopening 23 with the forward portion 25 of the shutter member 24 locatedtherein as would be the case of the shutter member 24 being influencedby fluid pressure. In this embodiment, the grooves are shown asgenerally triangular grooves 290, while in FIG. 9 the grooves are shownas generally circular ring sectiongrooves 29b. The grooves 29 may assumeother shapes as well, for example the shapes shown in FIGS. 10 and 11.

Instead of providing the grooves in the seating surface 27 of theopening 23 as shown in FIGS. 1-4 and 6-9, the grooves 29 as shown inFIG. 1 can be placed in the region of the bearing surface 30 of theshutter member 24. As examples of this embodiment, FIGS. 10 and l 1 showtwo different cross sections of the grooves located on the shuttermember 24. FIG. 10 illustrates rounded or generally semi-circulargrooves 29c, while FIG. 11 discloses circularly arcuated grooves 29d. Inthe latter case, these slitted grooves are formed by longitudinal ribs34 on the peripheral wall of the shutter member 24.

The embodiments of FIGS. 2 through 7 disclose the manner by which theshape of the shutter members may be varied and the manner by whichliquid jets of a predetermined pattern may be obtained by varying theparticular shape of the seating surface and/or the bearing surface ofthe shutter member. For simplicity, the nozzle bodies in FIGS. 3 through7, designated respectively by the reference numerals 45, 55, 65, andrespectively, are illustrated as a one-piece construction, while thebody of FIG. 2 is represented as a twopiece plastic-metal construction,designated b reference numerals 35 and 35a. However, in practice, thesebodies generally consist of two or more pieces, such as the embodimentsshown and described in connection with FIGS. 1 and 2. In addition,details of the inlet portion 17 and the inlet connection have beeneliminated to simplify reproduction of these embodiments. In eachinstance, the inlet conduit 20, the cavity 22, and the rear wall 31 havebeen designated by reference numerals corresponding to those utilized inconnection with FIG. I followed by the letters a through f in theembodiments of FIGS. 2-7 respectively. In each instance, the operationof the nozzle member is like that described in connection with FIG. 1.

In FIG. 2, the spray nozzle includes a generally spherically-shapedshutter member 36 disposed in the cavity 22a. The body 35a of the spraynozzle defines an opening 37 having a curved seating surface 38. Aplurality of spaced grooves 39 are located on the seating surface 38 andgenerally follow the contour of the curved seating surface 38. Thus,essentially cylindrical jets of liquid as indicated by the streamlines40 are obtained since the grooves 39 at the outlet portion of theopening 37 are substantially parallel.

In FIG. 3, the spray nozzle includes a generally spherical member 46similar to the spherical member 36 in FIG. 2 which cooperates with aconical seating surface 48 on the opening 47. The conical seatingsurface 48 defines a plurality of grooves 49. The opening 47 is furtherextended within the nozzle body which defines a generally tubular wallportion 50 defining an opening 51 which communicates with the opening47. The axial length of the opening 51 defined by the wall portion 50 isgreater than the distance of the focus 52 of the jets of fluid. Thus,the user can only utilize the diverging portion of the jets of liquid,the streamlines of which are designated generally by the referencenumerals 53. Such an embodiment is convenient when the user must excludethe possibility of unintentionally causing the focused, concentratedfluid to flow directly onto the gums, for example, where concentratedenergy could cause irritation. In such an embodiment, the force exertedby the diverging fluid is less than the force which would be exerted bythe fluid at the focal point 52.

In FIG. 4, the spray nozzle includes a shutter member designatedgenerally by the reference numeral 56 within the body 55 of the nozzle.The shutter member 56 includes a spherical head portion 57 whichcooperates with the seating surface 58 on the wall defining the opening59. The grooves 60 located on the seating surface 58 in the opening 59have a cross section which becomes wider outwardly in a conical form.Thus, the width of the grooves 60 at the outlet of the opening isgreater than at any inner portion of the grooves. The shutter member 56also includes a rearwardly extending protrusion 61 which presents arelatively flat surface 62 to the fluid (in a manner similar to a pistonface) which extends substantially over the largest portion of the crosssection of the internal cavity 22c of the nozzle body 55 andsimultaneously limits the inwardly extending clearance of the shuttermember.

The shape of the grooves 60 and the forward slightly curved region 63 ofthe limiting wall of the opening 59 generates liquid jets with anessentially parallel or cylindrical pattern as shown by the streamlines64 of the emerging jets of fluid.

The spray nozzle of FIG. has a shutter member 66 which includes aspherically-shaped head portion 67 having grooves 68 disposed thereinand a rearwardly directed protrusion 69. Structurally, the shuttermember 66 in FIG. 5 is similar to the structure of the shutter member 56in FIG. 4 but wherein the grooves 68 are located on the shutter memberrather than on the seating surface. The shutter member 66 cooperateswith the ungrooved conical seating surface 70 defining the opening 71 inorder to generate converging jets as designated by the streamlines 72having a focus at a point designated by the numeral 73. In theembodiment of FIG. 5, the rearward protrusion 69 on the shutter member66 and the rearwardly extending region of the cavity 22d defined by thenozzle body 65 are adapted to insure that the shutter member 66maintains the orientation needed for achieving the covering position andthat, when in this position, the grooves 68 are essentially parallelwith the central axis of the opening 71.

In FIG. 6, the spray nozzle includes a shutter member 76, the centralportion 77 of which is spherically curved and which cooperates with theconical seating surface 78 having grooves 79 therein. The shutter member76 further includes a forwardly extending protrusion 80 which projectsoutwardly into an opening 83 beyond the region of the seating surface78. The lastnamed protrusion generates diverging jets of fluid, shown bythe streamlines 82, because of its outwardly diverging shape. Theforward protrusion 80 may also be shortened or merged into a cylindricalprojection in such a way that a cylindrical jet of liquid is obtained,in a manner similar to the streamlines of FIGS. 2 and 4. The shuttermember 76 further includes a rearwardly extending protrusion 83 whichcooperates with the body 75 and the cavity 23e therein in a mannersimilar to that described in connection with FIGS. 4 and 5.

In FIG. 7, the spray nozzle includes a shutter member 86 which includesa rearwardly extending protrusions 87 and a conical forward portion 88which cooperates with the conical seating surface 89 defining theopening 90. The conical seating surface 89 defines a plurality ofgrooves 91 therein. The extent of the forward surface 94 of the forwardportion 88 of the shutter member 86 when positioned in the opening isslightly rearward of the forward surface 95 of the body 85. In thismanner, converging jets of fluid shown by the streamlines 92 will beobtained having a focus indicated by the reference numeral 93.

When the clearance available for the shutter member in any of theembodiments described in FIGS. 47 is a result of its rearward shaperelative to the shape of the rearwardly extending portion of the innercavity in the nozzle body and results in limiting the rearwardprotrusion so that the shutter when in a position covering the openingin the front portion of the nozzle body always takes the sameorientation, the grooves which form the nozzle apertures may also or inthe alternative be placed on the periphery of the shutter head. Inaddition, when the shutter member is a symmetrical body of revolution,as in the examples of FIGS. 1 and 47, the grooves, instead of beingprovided on the seating surface of the opening may be provided on theperiphery of the shutter member since the shutter member can essentiallyonly rotate about its axis of symmetry. When the seating surface alongwith the region of the bearing surface of the shutter member whichcooperates with the seating surface converges outwardly to a differentdegree as in the embodiments of FIGS. 1 to 6, there will be essentiallya line of contact between the shutter member and the seating surface inthe cover ing position so that the manufacture of the nozzle body and ofthe shutter members is not subject to substantial tolerance requirementsforthe primary reason that the shutter adjusts itself into the coveringposition.

The section of the grooves may be of any shape and particularly they maycorrespond to the shape shown in FIGS. 8 to 1 1. In addition, thegrooves may also diverge in the longitudinal direction.

The nozzle body and the shutter of the shutter member of the spraynozzle according to the invention are preferably made from plasticmaterial, although a plastic nozzle body having a metallic insertcorresponding to the forward housing 35a can also be used in practicingthe invention.

The invention may be embodied in other specific forms without departingfrom its spirit or essential characteristics. The present embodimentsare, therefore, to be considered in all respects as illustrative and notrestrictive, the scope of the invention being indi cated by the claimsrather than by the foregoing description, and all changes which comewithin the meaning and range of the equivalents of the claims aretherefore intended to be embraced therein.

What is claimed is:

11. A spray nozzle for expelling a fluid therefrom comprising:

a nozzle body which defines a cavity therein and includes a surfacewhich defines an opening communicating with the cavity and the exteriorof the nozzle body, at least a portion of said surface beingcharacterized as a seating surface, said nozzle body including fluidreceiving means for receiving a fluid under pressure, and freely-movableshutter member disposed in said cavity, said shutter member being freefrom permanent structural connection to said nozzle body and capable ofbeing located at least in a first position in said cavity substantiallyfree from structural contact with said seating surface on said opening,said shutter member including a bearing surface characterized as beingcapable of securely cooperating in a second position with said seatingsurface on said opening when said shutter member is subjected to a fluidpressure to cover substantially said opening to define in said secondposition at least a nozzle aperture for directing the passage of saidfluid from said cavity to the exterior of said nozzle body and fordirectly discharging a jet of said fluid from said nozzle body, saidnozzle aperture being readily accessible from the exterior of the nozzlebody when said shutter member is in said first position in the absenceof fluid pressure for cleaning said aperture and said nozzle body, saidfreelymovable shutter member being further characterized as beingfreely-movable from said first position to said second position underfluid pressure and capable of retreating from said bearing surface tosaid cavity in the absence of said fluid pressure to substantiallyuncover said opening.

2. The spray nozzle as set forth in claim 1 wherein either one of saidseating surface or said bearing surface includes at least a groovethereon, said groove defining said nozzle aperture when the bearingsurface of said shutter member cooperates in said second position withsaid seating surface when said nozzle member is subjected to said fluidpressure.

3. The spray nozzle as set forth in claim 2 wherein at least one of saidseating surface and said bearing surface taper outwardly so that atleast a portion of said shutter member can be engaged with said openingwithout expelling said shutter member from said nozzle till body whensaid shutter member is subjected to a fluid pressure.

4. The spray nozzle as set forth in claim 3 wherein said seating surfacetapers more rapidly than said bearing surface.

5. The spray nozzle as set forth in claim 4 wherein either of saidseating surface and said bearing surface is conical and the other iscurved in the direction of the escape of said fluid from said nozzlebody.

6. The spray nozzle as set forth in claim 4 wherein both of said seatingsurface and said bearing surface are curved in the direction of theescape of said fluid from said nozzle body.

7. The spray nozzle as set forth in claim 3 wherein both of said seatingsurface and said bearing surface are conical.

8. The spray nozzle as set forth in claim 3 wherein said shuttermemberis defined by a symmetrical body of revolution and said nozzle bodystructurally cooperates with said shutter member to maintain saidshutter member in a predetermined orientation relative to said opening.

9. The spray nozzle as set forth in claim 8 wherein said predeterminedorientation is maintained by the clearance between said nozzle body andsaid shutter member.

10. The spray nozzle as set forth in claim 8 wherein said shutter membercomprises a generally spherical forward portion and a generallycylindrical rearward portion, said shutter member further beingcharacterized as having a generally U-shaped axial cross section, saidforward portion extending into said opening when said shutter member issubjected to fluid pressure, and wherein stop means are provided in saidnozzle body for impeding the complete inward sliding of said shuttermember from said opening.

l1. The spray nozzle as set forth in claim 10 wherein said stop meanscomprise the inner wall of said nozzle body opposite said opening.

12. The spray nozzle as set forth in claim 3 wherein said shutter memberis sphericallyshaped.

13. The spray nozzle as set forth in claim 2 wherein said shutter memberincludes a rearwardly extending protrusion which cooperates with saidnozzle body to maintain said shutter member in a predetermined orientation relative to said opening.

14. The spray nozzle as set forth in claim 13 wherein said protrusion isgenerally piston-shaped and occupies the largest portion of the cavityin said nozzle body.

15. The spray nozzle as set forth in claim 13 wherein the portion of thecavity of said nozzle body which cooperates with said protrusion isshaped like said protrusion.

16. The spray nozzle as set forth in claim 1 wherein either one of saidseating surface or said bearing surface includes a plurality of groovesthereon, said grooves defining a plurality of nozzle apertures in saidnozzle body for the passage of a pllurality ofjets of fluid from saidcavity to the exterior of said nozzle body when said shutter membercooperates in said second position with said opening when subjected to afluid pressure, and wherein at least one of said seating surface andsaid bearing surface tapers outwardly so that at least a portion of saidshutter member can be engaged with said opening without expelling saidshutter member from said nozzle body when said shutter member issubjected to a fluid pressure.

17. The spray nozzle as set forth in claim 16 wherein said shuttermember is defined by a symmetrical body of revolution and said nozzlebody structurally cooperates with said shutter member to maintain saidshutter member in a predetermined orientation relative to said opening.

18. The spray nozzle as set forth in claim 17 wherein said predeterminedorientation is maintained by the clearance between said nozzle body andsaid shutter member.

19. The spray nozzle as set forth in claim 16 wherein said shuttermember comprises a generally spherical forward portion and a generallycylindrical rearward position, said shutter member further beingcharacterized as having a generally U-shaped axial cross section, saidforward portion extending into said opening when said shutter member issubjected to fluid pressure, and wherein stop means are provided in saidnozzle body for impeding the complete inward sliding of said shuttermember from said opening.

20. The spray nozzle as set forth in claim 19 wherein said stop meanscomprise the inner wall of said nozzle body opposite said opening.

21. The spray nozzle as set forth in claim 16 wherein said shuttermember is spherically-shaped and said grooves are provided in saidseating surface.

22. The spray nozzle as set forth in claim 16 wherein said shuttermember is spherically-shaped and said grooves are provided on saidshutter member.

23. The spray nozzle as set forth in claim 16 wherein said shuttermember includes a rearwardly extending protrusion which cooperates withsaid nozzle body to maintain said shutter member in a predeterminedorientation relative to said opening.

'24. The spray nozzle as set forth in claim 23 wherein said protrusionis generally piston-shaped and occupies the largest portion of thecavity in said nozzle body.

25. The spray nozzle as set forth in claim 23 wherein the portion of thecavity of said nozzle body which cooperates with said protrusion isshaped like said protrusion.

26. The spray nozzle as set forth in claim 16 wherein said seatingsurface and said bearing surface cooperate to produce a plurality ofjets of fluid which converge.

27. The spray nozzle as set forth in claim 26 wherein the focal pointfor the converging plurality of jets is located at a distance of about 8to 12 mm. from said nozzle.

28. The spray nozzle as set forth in claim 16 wherein said seatingsurface and said bearing surface cooperate to produce a plurality ofjets of liquid which are substantially parallel.

29. The spray nozzle as set forth in claim 16 wherein said seatingsurface and said bearing surface cooperate to produce a plurality ofjetsofliquid which form a generally cylindrical streamline.

30. The spray nozzle as set forth in claim 16 wherein said seatingsurface and said bearing surface cooperate to produce a plurality ofjets of liquid which diverge.

31. The spray nozzle as set forth in claim 16 wherein said seatingsurface and said bearing surface cooperate to produce a plurality ofjets of fluid which converge, and wherein said nozzle body defines agenerally tubular opening which communicates with said opening definedby said surface, the axial length of said opening being greater than thedistance of the focal point of the converging jets from the apertures ofsaid nozzle body.

32. The spray nozzle as set forth in claim 16 wherein said shuttermember includes an outwardly-extending protrusion which projectsoutwardly of said opening when said shutter member is subjected to fluidpressure.

33. The spray nozzle as set forth in claim 32 wherein saidoutwardly-extending protrusion cooperates with said opening to produce aplurality ofjets of fluid which diverge.

34. The spray nozzle as set forth in claim 16 wherein thecross-sectional configuration of said grooves is any one of thefollowing: round triangular, rectangular, or circularly arcuate.

35. The spray nozzle as set forth in claim 16 wherein the cross-sectionof said grooves diverges in the longitudinal direction of said seatingsurface of said opening.

36. The spray nozzle as set forth in claim 16 wherein said nozzle bodyand said shutter member are made from plastic material.

37. The spray nozzle as set forth in claim 16 wherein said nozzle bodyis defined by a first member made from plastic and a second member madefrom metal and said second member defines said opening.

38. The spray nozzle as defined in claim 1 wherein said spray nozzle isparticularly adapted for cleaning the teeth and massaging the gums bythe use of said fluid.

39. The spray nozzle as defined in claim 16 wherein said spray nozzle isparticularly adapted for cleaning the teeth and massaging the gums bythe use of said fluid.

40. The spray nozzle as set forth in claim 1 in combination with:

a source of fluid, and

means for providing said fluid under pressure from said source to saidnozzle body.

41. A method for expelling a fluid from a nozzle body comprising thesteps of:

providing a source of fluid to a nozzle body which defines a cavitytherein and includes a surface which defines an opening communicatingwith the cavity and the exterior of the nozzle body, at least a portionof said surface being characterized as a seating surface, said nozzlebody including fluid receiving means for receiving said fluid underpressure, a freely-movable shutter member disposed in said cavity, saidshutter member being free from permanent structural connection to saidnozzle body and capable of being located at least in a first position insaid cavity substantially free from structural contact with said seatingsurface on said opening, said shutter member including a bearing surfacecharacterized as being capable of securely cooperating in a secondposition with said seating surface on said opening when said shuttermember is sub jected to a fluid pressure to cover substantially saidopening in said second position to define at least a nozzle aperture fordirecting the passage of said fluid from said cavity to the exterior ofsaid nozzle body, and for directly discharging a jet of said fluid fromsaid nozzle body, said nozzle aperture being readily accessible from theexterior of the nozzle body when said shutter member is in said firstposition in the absence of fluid pressure for cleaning said aperture andsaid nozzle body, said freely-- movable shutter member being furthercharacterized as being freely-movable from said first position 14cluding the step of utilizing said jet for body care.

43. The method as set forth in claim 42 wherein the step of utilizingincludes the step of cleaning the teeth. 44. The method as set forth inclaim 42 wherein the step of utilizing includes the step of massagingthe gums.

1. A spray nozzle for expelling a fluid therefrom comprising: a nozzlebody which defines a cavity therein and includes a surface which definesan opening communicating with the cavity and the exterior of the nozzlebody, at least a portion of said surface being characterized as aseating surface, said nozzle body including fluid receiving means forreceiving a fluid under pressure, and a freely-movable shutter memberdisposed in said cavity, said shutter member being free from permanentstructural connection to said nozzle body and capable of being locatedat least in a first position in said cavity substantially free fromstructural contact with said seating surface on said opening, saidshutter member including a bearing surface characterized as beingcapable of securely cooperating in a second position with said seatingsurface on said opening when said shutter member is subjected to a fluidpressure to cover substantially said opening to define in said secondposition at least a nozzle aperture for directing the passage of saidfluid from said cavity to the exterior of said nozzle body and fordirectly discharging a jet of said fluid from said nozzle body, saidnozzle aperture being readily accessible from the exterior of the nozzlebody when said shUtter member is in said first position in the absenceof fluid pressure for cleaning said aperture and said nozzle body, saidfreely-movable shutter member being further characterized as beingfreely-movable from said first position to said second position underfluid pressure and capable of retreating from said bearing surface tosaid cavity in the absence of said fluid pressure to substantiallyuncover said opening.
 2. The spray nozzle as set forth in claim 1wherein either one of said seating surface or said bearing surfaceincludes at least a groove thereon, said groove defining said nozzleaperture when the bearing surface of said shutter member cooperates insaid second position with said seating surface when said nozzle memberis subjected to said fluid pressure.
 3. The spray nozzle as set forth inclaim 2 wherein at least one of said seating surface and said bearingsurface taper outwardly so that at least a portion of said shuttermember can be engaged with said opening without expelling said shuttermember from said nozzle body when said shutter member is subjected to afluid pressure.
 4. The spray nozzle as set forth in claim 3 wherein saidseating surface tapers more rapidly than said bearing surface.
 5. Thespray nozzle as set forth in claim 4 wherein either of said seatingsurface and said bearing surface is conical and the other is curved inthe direction of the escape of said fluid from said nozzle body.
 6. Thespray nozzle as set forth in claim 4 wherein both of said seatingsurface and said bearing surface are curved in the direction of theescape of said fluid from said nozzle body.
 7. The spray nozzle as setforth in claim 3 wherein both of said seating surface and said bearingsurface are conical.
 8. The spray nozzle as set forth in claim 3 whereinsaid shutter member is defined by a symmetrical body of revolution andsaid nozzle body structurally cooperates with said shutter member tomaintain said shutter member in a predetermined orientation relative tosaid opening.
 9. The spray nozzle as set forth in claim 8 wherein saidpredetermined orientation is maintained by the clearance between saidnozzle body and said shutter member.
 10. The spray nozzle as set forthin claim 8 wherein said shutter member comprises a generally sphericalforward portion and a generally cylindrical rearward portion, saidshutter member further being characterized as having a generallyU-shaped axial cross section, said forward portion extending into saidopening when said shutter member is subjected to fluid pressure, andwherein stop means are provided in said nozzle body for impeding thecomplete inward sliding of said shutter member from said opening. 11.The spray nozzle as set forth in claim 10 wherein said stop meanscomprise the inner wall of said nozzle body opposite said opening. 12.The spray nozzle as set forth in claim 3 wherein said shutter member isspherically-shaped.
 13. The spray nozzle as set forth in claim 2 whereinsaid shutter member includes a rearwardly extending protrusion whichcooperates with said nozzle body to maintain said shutter member in apredetermined orientation relative to said opening.
 14. The spray nozzleas set forth in claim 13 wherein said protrusion is generallypiston-shaped and occupies the largest portion of the cavity in saidnozzle body.
 15. The spray nozzle as set forth in claim 13 wherein theportion of the cavity of said nozzle body which cooperates with saidprotrusion is shaped like said protrusion.
 16. The spray nozzle as setforth in claim 1 wherein either one of said seating surface or saidbearing surface includes a plurality of grooves thereon, said groovesdefining a plurality of nozzle apertures in said nozzle body for thepassage of a plurality of jets of fluid from said cavity to the exteriorof said nozzle body when said shutter member cooperates in said secondposition with said opening when subjected to a fluid pressure, andwherein at least one of said seating surfaCe and said bearing surfacetapers outwardly so that at least a portion of said shutter member canbe engaged with said opening without expelling said shutter member fromsaid nozzle body when said shutter member is subjected to a fluidpressure.
 17. The spray nozzle as set forth in claim 16 wherein saidshutter member is defined by a symmetrical body of revolution and saidnozzle body structurally cooperates with said shutter member to maintainsaid shutter member in a predetermined orientation relative to saidopening.
 18. The spray nozzle as set forth in claim 17 wherein saidpredetermined orientation is maintained by the clearance between saidnozzle body and said shutter member.
 19. The spray nozzle as set forthin claim 16 wherein said shutter member comprises a generally sphericalforward portion and a generally cylindrical rearward position, saidshutter member further being characterized as having a generallyU-shaped axial cross section, said forward portion extending into saidopening when said shutter member is subjected to fluid pressure, andwherein stop means are provided in said nozzle body for impeding thecomplete inward sliding of said shutter member from said opening. 20.The spray nozzle as set forth in claim 19 wherein said stop meanscomprise the inner wall of said nozzle body opposite said opening. 21.The spray nozzle as set forth in claim 16 wherein said shutter member isspherically-shaped and said grooves are provided in said seatingsurface.
 22. The spray nozzle as set forth in claim 16 wherein saidshutter member is spherically-shaped and said grooves are provided onsaid shutter member.
 23. The spray nozzle as set forth in claim 16wherein said shutter member includes a rearwardly extending protrusionwhich cooperates with said nozzle body to maintain said shutter memberin a predetermined orientation relative to said opening.
 24. The spraynozzle as set forth in claim 23 wherein said protrusion is generallypiston-shaped and occupies the largest portion of the cavity in saidnozzle body.
 25. The spray nozzle as set forth in claim 23 wherein theportion of the cavity of said nozzle body which cooperates with saidprotrusion is shaped like said protrusion.
 26. The spray nozzle as setforth in claim 16 wherein said seating surface and said bearing surfacecooperate to produce a plurality of jets of fluid which converge. 27.The spray nozzle as set forth in claim 26 wherein the focal point forthe converging plurality of jets is located at a distance of about 8 to12 mm. from said nozzle.
 28. The spray nozzle as set forth in claim 16wherein said seating surface and said bearing surface cooperate toproduce a plurality of jets of liquid which are substantially parallel.29. The spray nozzle as set forth in claim 16 wherein said seatingsurface and said bearing surface cooperate to produce a plurality ofjets of liquid which form a generally cylindrical streamline.
 30. Thespray nozzle as set forth in claim 16 wherein said seating surface andsaid bearing surface cooperate to produce a plurality of jets of liquidwhich diverge.
 31. The spray nozzle as set forth in claim 16 whereinsaid seating surface and said bearing surface cooperate to produce aplurality of jets of fluid which converge, and wherein said nozzle bodydefines a generally tubular opening which communicates with said openingdefined by said surface, the axial length of said opening being greaterthan the distance of the focal point of the converging jets from theapertures of said nozzle body.
 32. The spray nozzle as set forth inclaim 16 wherein said shutter member includes an outwardly-extendingprotrusion which projects outwardly of said opening when said shuttermember is subjected to fluid pressure.
 33. The spray nozzle as set forthin claim 32 wherein said outwardly-extending protrusion cooperates withsaid opening to produce a plurality of jets of fluid which diverge. 34.The spray nozzle as set forth in claim 16 wherein the cross-sectionalconfiguration of said grooves is any one of the following: roundtriangular, rectangular, or circularly arcuate.
 35. The spray nozzle asset forth in claim 16 wherein the cross-section of said grooves divergesin the longitudinal direction of said seating surface of said opening.36. The spray nozzle as set forth in claim 16 wherein said nozzle bodyand said shutter member are made from plastic material.
 37. The spraynozzle as set forth in claim 16 wherein said nozzle body is defined by afirst member made from plastic and a second member made from metal andsaid second member defines said opening.
 38. The spray nozzle as definedin claim 1 wherein said spray nozzle is particularly adapted forcleaning the teeth and massaging the gums by the use of said fluid. 39.The spray nozzle as defined in claim 16 wherein said spray nozzle isparticularly adapted for cleaning the teeth and massaging the gums bythe use of said fluid.
 40. The spray nozzle as set forth in claim 1 incombination with: a source of fluid, and means for providing said fluidunder pressure from said source to said nozzle body.
 41. A method forexpelling a fluid from a nozzle body comprising the steps of: providinga source of fluid to a nozzle body which defines a cavity therein andincludes a surface which defines an opening communicating with thecavity and the exterior of the nozzle body, at least a portion of saidsurface being characterized as a seating surface, said nozzle bodyincluding fluid receiving means for receiving said fluid under pressure,a freely-movable shutter member disposed in said cavity, said shuttermember being free from permanent structural connection to said nozzlebody and capable of being located at least in a first position in saidcavity substantially free from structural contact with said seatingsurface on said opening, said shutter member including a bearing surfacecharacterized as being capable of securely cooperating in a secondposition with said seating surface on said opening when said shuttermember is subjected to a fluid pressure to cover substantially saidopening in said second position to define at least a nozzle aperture fordirecting the passage of said fluid from said cavity to the exterior ofsaid nozzle body, and for directly discharging a jet of said fluid fromsaid nozzle body, said nozzle aperture being readily accessible from theexterior of the nozzle body when said shutter member is in said firstposition in the absence of fluid pressure for cleaning said aperture andsaid nozzle body, said freely-movable shutter member being furthercharacterized as being freely-movable from said first position to saidsecond position under fluid pressure and capable of retreating from saidbearing surface to said cavity in the absence of said fluid pressure tosubstantially uncover said opening; and causing said fluid to pass underpressure from said source of fluid through said nozzle aperture toproduce said jet.
 42. The method as set forth in claim 41 furtherincluding the step of utilizing said jet for body care.
 43. The methodas set forth in claim 42 wherein the step of utilizing includes the stepof cleaning the teeth.
 44. The method as set forth in claim 42 whereinthe step of utilizing includes the step of massaging the gums.